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RESULTS <br />K f~}J <br />Habitat Features <br />r <br />A total 729 backwater and low velocity flow habitats were sampled between June 1994 <br />and September 1996. (For simplicity, and because the overwhelming majority were backwaters <br />rather than low velocity flow habitats, these will hereafter be called backwaters.) Numbers of <br />backwaters sampled varied between years and seasons (Table 2). The predominant backwater <br />class was shoreline eddy. This class accounted for 36.2% (n=264) of all sampled sites. Scour <br />(side channel) habitats and constricted reach eddies were the next most numerous backwater types <br />at 26.5% (n=193) and 25.9% (n=187), respectively. Migrating sand wave backwaters accounted <br />for another 9.2% (n=67) of all backwaters sampled. The remaining 2.2% (n=15) of .sampled <br />r <br />habitats were composed of horseshoe vortex, isolated pool, low velocity flow and shoreline <br />backwaters. <br />Associations between flow events and backwater numbers could not be rigorously tested <br />because this study represents only three years of flow data. Regression analysis with only three <br />data points is highly suspect. Likewise, correlation analysis with only 2 df may not be completely <br />descriptive. In addition, because only two data sets were available for April and July sampling, <br />and one for June, no tests could be run for backwater/flow correlations for these months. None- <br />the-less, correlation analyses were run to determine if backwater types were influenced by flow <br />events. Strong negative correlations were seen between the number of migrating sand wave <br />backwaters sampled and annual peak flow (r 0.61) and the duration of flow above 50% of the <br />peak (r=--0.62) when all sampling periods were included in the analysis. <br />11 <br />